package com.itheima.filter;

import com.itheima.util.JwtUtils;
import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.StringUtils;

import java.io.IOException;

@Slf4j
@WebFilter(urlPatterns = "/*")
public class TokenFilter implements Filter {
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        //1.获取请求url。
        String url = request.getRequestURL().toString();
        //2.判断请求url中是否包含login，如果包含，说明是登录操作，放行。
        if (url.contains("/login")){
            log.info("这是一个登录请求，放行");
            filterChain.doFilter(request, response);
            return;
        }
        //3.获取请求头中的令牌（token）。
        String jwt = request.getHeader("token");
        //4，判断令牌是否存在，如果不存在，响应401。
        if(!StringUtils.hasLength(jwt)){
            response.setStatus(401);
            return;
        }
        //5.解析token，如果解析失败，响应401
        try {
            JwtUtils.parseJWT(jwt);
        } catch (Exception e) {
            e.printStackTrace();
            log.info("解析令牌失败");
            response.setStatus(401);
            return;
        }
        //6.放行。
        filterChain.doFilter(request, response);
    }
}
